Takedown mechanism for firearms



D. M. WILLIAMS TKEDOWNA MECHANISM FOR FIREARMS May 25, 1954 2 Sheets-Sheet l Filed Aug.` 20, 1948 May 25, 1954 D. M. WILLIAMS 2,679,123

TAKEDowN MECHANISM FoR FIREARMS Filed Aug, 20, 1948 2 sneaks-sheet 2 Patented May 25, 1954 TAKEDOWN MECHANISM FOR- FIREARMS David M. Williams, New Haven, Conn., assgnor to Olin Industries, Inc., New Haven, Conn., a

corporation of Delaware Application August 20, 1948, Serial No. 45,243

7 Claims. (Cl. 42-75) The present invention relates in general to firearms and more especially to a firearm of the takedown type, that is to say, a firearm in which the frame and barrel are readily separable one from the the other for convenience in packing, shipping and carrying.

An object of the invention is to provide a firearm with superior takedown-means for readily attaching the barrel to the frame of the firearm and detaching it therefrom.

A further object of the invention is to provide a takedown firearm having superior takedownmeans for attaching and detaching the barrel to and from the frame of the firearm, the takedownl means being of durable and dependable construction which lends itself to simplicity and facility of operation.

A still further object of the invention is to provide a retractable operating-means for the takedown mechanism of a firearm vwherein the operating-means in its normal locked position is retracted into a recess of the fore-end and is resiliently held therein from outward displacement.

With the above and other .objects in view, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

Fig'. l is a broken side elevation of a firearm embodying the improved takedown mechanism of this invention, tne fore-end of the firearm including the takedown-means being shown partly in section to demonstrate the relationship between the barrel, fore-end and frame-unit;

Fig. 2 is a fragmentary bottom view of the forward end of the fore-end of Fig. 1;

Fig. 3 is a broken side elevation of the firearm similar to Fig. 1 except that the takedown mechanism is shown disconnected from the barrel locking-lug and the magazine-plug;

Fig. 4 is an end elevation of the firearm in the direction of arrows 4-4 of Fig. 3;

Fig. 5 is a top plan view of the takedown mechanism on section line 5-5 of Fig. 1;

Fig. 6 is an end elevation in section on line ii-- of Fig. 1; 1 I Y Fig. 7 is an end elevation on section line 'I-'I of Fig. l;

Fig. 8 is an end elevation on section line .8- of Fig. 1;

Fig. 9 is a perspective view of the improved takedown mechanism of the invention;

Fig. 10 is a perspective view in longitudinal section of the sliding link-member of the takedown mechanism;

Fig. 11 is a perspective view of the lockingblock of the takedown mechanism looking toward the rear of the block; and

Fig. 12 is a perspective view of the locking-block of the takedown mechanism looking towards the front of the block.

The particular takedown rearm herein chosen for illustrating the invention, includes two principal units which are separable one from the other to enable the firearm to be more conveniently packed, shipped or carried. The one unit of the firearm may, for convenience of description, be designated as the frame-unit and comprises, in the main, the receiver I5, a tubular magazine i5 rigidly secured at its rear end to the forward end of the receiver by a substantially-permanent connection and a fore-end I'I. The complementary barrel-unit of the firearm comprises, in the main, a barrel I8 having interrupted threads at its read end adapted to be detachably coupled with corresponding interrupted threads of a longitudinal aperture in the front face of the receiver in a manner well known in the art; and a barrel locking-lug indicated generally at I9. The latter is a substantially L-shaped member having a long leg 22) xedly secured to the underside of the barrel substantially longitudinally thereof, and an apertured short leg 2I extending substantially at right angles to the long leg 20 and adapted to project downwardly from the underside of the barrel, for the purpose hereinafter described.

Referring especially to Fig. 1, it will be noted that when the barrel I8 and the fore-end I1 are assembled on the frame-unit, the short leg 2| is adapted to extend downwardly into a vertical clearance-recess 22 at the forward end of a longitudinal magazine-receiving aperture 23 of the fore-end and immediately in front of the forward end of the tubular magazine. The forward end of the latter is enclosed by a solid plug 24 which is pinned or otherwise fixedly secured therein and provided with a smooth-bored aperture or socket 25. The latter intersects the front face of the plug 24 and extends rearwardly therein substantially parallel with but eccentric to the longitudinal axis of the magazine and constitutes a connecting element of the takedown mechanism, as hereinafter described.

The fore-end I'I is substantially U-shaped in cross section, its rear end being provided with a. U-shaped shoulder 26, in cameo, arranged to seat in a recess 21 of the corresponding shape and counterbore 3| of the fore-end and the semicircular counter-bore 52 of the locking-block so as to make a snug flt therein, the over-all length of the barrel-portion 56 of the bushing corresponding substantially to the distance from the front end of the fore-end to the front face of the tongueportion of the locking-block. The rear end of the barrel-portion 5S of the bushing forms an annular substantially-square shoulder 58 with its integral hollow shank-portion 5'?, the annular square shoulder 58 being adapted to abut against the front face of the tongue 41 of the locking-block when the bushing is assembled therein to hold the bushing from moving rearwardly in the locking-block. To positively secure the bushing 1n the locking-block, a screw 59 is adapted to be inserted into the vertical aperture 5i! in the headportion of the locking-block and to threadedly engage in an internally-threaded substantiallyvertical aperture 60 in the rear wall 62 of the barrel-portion 55 of the bushing, as shown especially well in Figs. 1 and '7. In this connection, it will be noted that the cylindrical bore 6i of the barrel-portion of the bushing is terminated forwardly of its annular square shoulder 58 sufficiently distant to provide the barrel with the relatively-thick substantially-flat rear Wall 62 which is apertured centrally by an extension of the bore E3- of the shank 5'! to form a forwardlyfacing substantially-square internal shoulder 64 at the rear end of the barrel bore. Formed in the bottom of the barrel-portion of the bushing and extending forwardly longitudinally from its internal shoulder 64 to the forward end of the bushing is a relatively-narrow slot B5 which is substantially equal in width to the vertical slots 53 and 32 of the locking-block and fore-end respectively and is adapted to accommodate the operating-lever of the takedown connector d3, as hereinafter described.

When assembled and secured in the fore-end by means of the locking-block as described above, the takedown bushing 42 is adapted to support the takedown connector 43 for effecting a substantially-rigid connection between the barrelunit and frame-unit and which is shown especially well in Fig. 9, comprises a screw having a substantially cylindrical body-portion 66 provided with a substantially-square end wall Sii', the body-portion 66 of the screw being dimensioned diametrically so as to make a smooth-l sliding flt in the bore 5l of the bushing and longitudinally substantially equal in length to the barrel-portion 56 thereof. Formed integrally on the rear end of the body-portion 66 of the slidable solid cylindrical stem-portion 61, the center portion 68 thereof intermediate its opposite ends being substantially equal in diameter to the diameter of the bore 63 of the hollow shank 5l of the bushing so as to make a smooth-sliding lt therein. The opposite ends 65 and 'ill respectively of the stem B'i are of reduced diameter, the former to provide clearance normally within the hollow shank of the bushing opposite the bushing retaining-screw 59 whereby the lower end of the latter is adapted to project down into the clearance-space to engage the forwardly-facing shoulder of the reduced end 59 of the stem-portion of the screw to prevent the screw from sliding forwardly out of the bushing when disconnected from the barrel locking-lug I9. Abutment of the end wall 66 of the body-portion B6 of the takedown screw against the forward-facing shoulder 64 of bushing 42 provides a stop for the rearward longitudinal movement of the takedown screw. By this means the screw is constrained for rotational and limited longitudinal movement both fore and aft within the fore-end. The rear end le of the stem is reduced in diameter so as to t snugly in the aforesaid eccentric longitudinally-extending aperture or socket 25 in the magazine-plug. In this respect, both the rear end 'ill of the stem and the aperture 25 of the magazine-plug constitute connecting elements, both for insuring alignment of the fore-end with the magazine and a substantially-rigid connection therebetween. The external threads H at the rear end of the center portion 68 of the screw are adapted to be threadedly engaged in an internally-threaded aperture 12 formed in the short leg 2| of the barrel-lug for locking the barrelunit to the frame-unit, as hereinafter described. Referring to Figs. 4, 5, 6 and 9, the aforesaid body-portion 66 of the takedown screw is provided with a substantially-vertical slot 'i3 which extends from the front end thereof rearwardly and terminates in a substantially-vertical rear wall 'i4 forwardly of the rear end of the bodyportion 65, the corners at the upper and lower ends of the aforesaid wall being beveled downwardly and forwardly as indicated at l5 and i6 respectively, to provide clearance for the operating-lever of the takedown screw, as hereinafter described. Moreover, the aforesaid vertical rear wall 14 of the slot is intersected by the forward end of a longitudinal aperture 'i1 which eX- tends from the front face of the wall rearwardly substantially half the length of the solid stemportion 6l of the screw to accommodate a coilspring 'i8 and to provide a guide-passage for a spring-loaded plunger 13. The rear end of the latter is adapted to engage against the forward end of the coil-spring, while the forward end of the plunger is adapted to extend forwardly beyond the substantially-vertical rear wall 'i4 of the aforesaid slot, both when the spring is compressed as shown in Fig. 1 and when it is expanded as shown in Fig. 3.

The spring and spring-plunger constitute elet ments of a latch mechanism for releasably holding the operating-member of the takedown screw in the aforesaid T-shaped slot of the fore-end, the other elements of the latch mechanism cornprising a link-member Si) slidably mounted in the slot 13 of the body-portion 65 of the screw for longitudinal movement therein, and consisting of two relatively-thin hat leaves 8l, each leaf being substantially equal in length to the length of the slot 13. Moreover, each leaf is substantially equal in width to the diameter of the body 66 of the screw, while the upper and lower edges of each leaf are beveled to conform with the periphery thereof. These leaves are adapted to be spaced apart in substantially parallel relationship by an integral spacer-block 82 formed between the leaves at the rear ends thereof, the spacerblock having a substantially-vertical rear face 83 adapted to be opposed to the vertical wall 74 of the slot 'i3 when the link-member Sil is mounted therein and to be engaged by the forward end of the spring-plunger i9. The upper and lower edges 84 and 85 respectively of the spacer-block are tapered downWardly-and-forwardly and upwardly-and-forwardly respectively to a degree to intersect at their forward ends in an apex on substantially the longitudinal axis of the link-member, thereby to provide clearance for actuation of the operating-member of the takedown screw, as hereinafter described. As shown especially well in Fig. 10, an aperture 86 is formed aaevogaas giti'ldinallyirithe'vertieal slot fi3 thereof and for l? :biting itslongitudinarmcveinenttherein. i The forward vlends of-thespaced-parallel leaves i of ithe?linli-mernber arerheld in spaced-parallel re- -latoship f by 'the-inner vend of! Athe takedown- 'ls'crew opera-tinglmember lie, 'which comprises Aa l"'-lev'e the in-nerl end-10i which is `pivotally' secured -be't'ween the forward ends* of the leaves" by a transverse' pivot-pin 9 i.

:The operating-lever 9a is of substantially-unii-'fornithickness throughout-its length,- its` thickness being only'- sliglitly :less than the transverse ""spaeing of the leaves of the link-'member andthe vwidths of the respectiveslots, 32 and 5 of-the bushing, fore-end and locking-block". Thusjwhen -''the'link-member 3G and `its pivotedf operating- 'leverl aremcunted in the slot 'i3 of the takedownscrew,- the operating-lever may oe Vswung fr'e'ely back 'and forth' inthe longitudinal; coincidental slots 65 and-S2 ofthebushing and-fore- "endffor" the purpose" hereinafter described, the lfaforesad tapered upper-*and lower edges of the spacer-block 82 'and theupperand lower beveled corners of the rear ywall I4 of `the-slot 'i3 providing l" clearancefor the operating-lever las-in:ic.`fitedresl'f-pecially well i' in Ylig. l.

EYReferring to Figs. 1v, 2,4, 8 and 9, the outer end of thefoperating-lever is seen to be provided with La transverse'latch-bar 92, the transverselhar be- `-ing substantially semi-cylindrical in shape with lfits?'reaivsubstantially-flat face provided with a longitudinal groovel-SS- substantially U -shaped in cross section as and -for the purpose-hereinaftei f described. Moreover, the transverse latch-bar i of"Y the operating-lever is dimensioned to correfspo'nd substantiallytothev sizeof the shouldered recess-Edin the back-vof -thetongue"p0frtion 4T of Jthe locking-block so -as 'to-fit nicely therein ywith -'its 'l cylindrical fronti face inengagement? -with the `front faceof -thei shouldered recess andthe -il-adjac'ent portion of the operating-lever engaging' inthe slot of Vthe tongue. Thel'over-ali length' of' the V-operating-l'ever is such' that' when ythe 2link-member of fthe latch mechanisml is re- Qfsi-liently'held by the spring! i8 andvspring-plunger at-the limit of itsforwa-rd movement in the slot -13 of the takedown screw; as determinedfby `fer'igagernent of therear'- end ofthe-guide-slotl lf'thelink-n'iember with the transverse-limitpin'89, asfshown in Fig. 3, the' reach'of the operat- "ing-lever isi less than that requiredv--to-'fenga'ge its latch-bar 92 in the shouldered-'recess-541m the back facev of the locking-block. However, Aloy '1 pressing rearwardly onthe front vend of thelinkmember to; compress the springl the-link- "meinber may be pushed rearwardly initlieY slot 73 to` its-rearmost position to bringthe latch-bar 92'ofA the operating-leverfbehind the'frontfaee A'of vthe-recess 54 of the*locking-block,\tfhereby the la'tch-har may be swung-uplintootheslot. ofthe l yfore-end into engagement-with the shouldered re'cess ofk the. locking-block. Then.'on-releasing "fthe forwardiend of the' linli-n'ieinbeni ,thef force 1 of-the'compressed spring" i 8 acting Jthrough fensorewllaoth' -for- 'guiding-the linie-inemb er 831 lon- `face ltof fthe linie-membeiaends' to 'urge vthe :latvv-'terf forwardly and hence-1toresiliently 'hold A.the 'i ftransverseilatch-bai' rmlyzaga'instzthe front yface of the recess? `l54,f'the`rel1y to 'frictionallyretain the operating-lever? in its latched or yinoperative #position iin-the slotf of the' fore-end," as 'f shown win 'Figli-1.

l'Iheoperation.' offthe takedo'wn mechanism is 'fbriefly as follows. `vAssuming the frame-unit and loi barrel-unitof the iirearm are disassembled Eand that thejscrew '4 3" of theItaliedown"I mechanism? of #thefore-end fis out oi engagement 'with -the lock- `ing-lug of the barrel,the-operating-lever'f90of -thel takedownA mechanismbeing' unlatched from 'isi-the -locking-block-44; as shown in Figs; Buand 4; u -the'first steam-assembling the vunits is to engage fthe-'interrupted threads 'atthe're'arfend 'ofthe `harrel -withthe interriu''ptedv threads-*on the interior ofthe barrel-receiving aperture-iin `'the' front 'wall 'lol' of the receiver'- to--couplel'the bar-rel v"the'r'eto,' `the coupling of {the respective fthreads" being effected by' 'r'otating-thel `barrel' through substantially! '90 relative tothe receiver, the locking-lug lof thebarlrel-being simultaneously movedfinto af'v'ertical plane-immediately-beneath thelunders'ide'thereof andlinf registration fwith4 the? front'-ehdof the Airlzugfaz'ine. Thereafter, the 'fore-end 'I 'l isslipped `over the "forward end of? the tubular fmaga'z'ine `i andl moved'A rearwardly-v th'ereon =to "seat? the so cameo shoulder? -ZS- at? itherearfend *ofi the' Aforeendin'the recess-2116i the: frbntlface'of the re- -ceiven The elements Vvof ltheassembly are then inthe positions indicated in" Fig.- 3 Ain Lwhich the 'rear' end 'I0 of the*tak'edowny lse-re'wis ini 'axial alignment with both the *internally-threaded aperture" l2 ofthe barrel locking-lug vI9 and the longitudinal aperture' 25j of the magazine-plug- 24. The operator then "grasps `the lunlat'olied' operating-lever-SO ofv the" taked'own-'screw 'and' rotates 40 the latter in a clockwise direction," Vas viewedl in Fig. 4;' while1 simultaneously Epressing'rearwardly on theA link-member 80-so as to' 'engage the threads 'H v of 'the screw'in the internally-threa''iedapertureY '12"of the barrel locking'v-lugiS. *Since vthe .1:1 takedown screw vis effectively held frommoving rearwardly in the Lbushingby' engagement of the 'square-'shoulder' 65at1the rear'nd of 'its bdyportion 66:with"theinternalffshulder-G4 'of the bushing, conti'riuedrot'ati'on ofthe operating-'lever ,-Oftal'ces upvanyslacl; between 'theinteirupted threads of thebarrell and receiver sofas to form ai tight' connection therebetween and thereafter the fore-end l1 is drawn rearwardly with respect to the harrell'llj 'soas to' firmly seat the cameo 55, shoulderZSof the fore-end'in the aforesaid reoess'2'iof the receiver. "Simultaneously, thereduced' rear'en'd lll'of the screw 43 enters 'into the aperture 25 of the'magazineeplug to make a' substantially-rigid connection o'etween theforward g4) lend 'thereof and therme-end Il. Consequently,

"thebarrel-unit'and fiarne-uiiitare rigidly con- "ne'e't'edtogether, the 'barrel being positively held from 'rotation about its longitudinalaxisby engagement oithewtaked'own screw in the locking- @5 lug' thereof, the ftakedown's'crew '43it'self vbeing held' se'curelyagainst longitudinal movementlzby Vreason of the tension'develofied'iri the connection between the harrell-unit and the frame-unit. 'Now the l one'rator may swing. the pivoted' operating- 70 lever ilupwaidly"intothe' slot 32 Vofthe foreend andby pressing rearwardlyon the forward end offthe link-memberf; slidev thellatter rearwardly intheA slotflof the fixed screw-"13 so that tthe latch-barfSZ of-^theleveri-mayffengage the A-forward and upperfiaces--of the recess' E4 iin-the rear face of the tongue of the locking-blockl whereby the operating-lever will be effectively held up in the slot 32 of the fore-end in its retired position by the force of the compressed spring 'i8 as hereinabove described. In its retired position, the operating-lever will be seen to be Withdrawn into the longitudinal slot 32 of the fore-end so as to be wholly unexposed, and hence is fully protected from accidental injury and inadvertent release.

To release the operating-lever 90, the shooter may engage his fingernail or the rim of a cartridge in the transverse groove 93 of the latchbar 92, which is facilitated by the beveled edge 34 of the aperture 33 in the underside of the fore-end, to pry the latch-bar 92 of the operating-lever downwardly out of frictional engagement with the shouldered recess 54 in the rear face of the tongue 41 of the locking-block, whereupon the force of the compressed spring 18 of the latch mechanism pushes the link-member 80 forwardly in the slot 13 of the takedown screw 4'3 to carry the pivoted end 9| of the operating-lever forwardly out beyond the front end of the fore-end l1 and its bushing 42 to a position as indicated by the broken lines in Fig. 1, at which it is stopped by coaction of the limitpin 39 with the guide-slot 81 of the link-member. The operating-lever then hangs down in its operating position clear of the fore-end and at substantially right angles to the screw. Hence, by rotating the operating-lever counterclockwise, the threaded end of the screw may be disengaged from the locking-lug I9 of the barrel for disassembling the barrel-unit and the frame-unit of the rearm.

The invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are in tended to be embraced therein.

I claim:

l. A takedown firearm, including in combination: a barrel-unit having a barrel-locking lug; a frame-unit including a tubular magazine having a connecting-element at the forward end thereof; a slotted fore-end arranged to cooperatively engage said frame-unit and said barrelunit; and takedown-means mounted in said slotted fore-end, said takedown-means comprising a locking-block secured in said fore-end and having a shouldered recess coextensive with the slot of said fore-end, a screw extending longitudinally through said locking-block and arranged to engage the said locking-lug of said barrel-unit and the connecting-element of said tubular magazine to releasably secure said barrel-unit substantially rigidly to said frame-unit, and an operating-lever for operating said takedown-screw, said operating-lever being arranged to lie in the slot of said fore-end in releasable engagement with the shouldered recess of said locking-block when in its normal inoperative position and to be withdrawn from said slot for operating said screw.

2. A takedown firearm, including in combination: a barrel-unit having a barrel-locking lug; a frame-unit including a tubular magazine having a connecting-element at the forward end thereof; a slotted fore-end arranged to cooperatively engage said frame-unit and said barrelunit; and takedown-means mounted in said slotted fore-end, said takedown-means comprising a locking-block secured in said fore-end and having a shouldered recess coextensive with the slot of said fore-end, a screw extending longitudinally through said locking-block and arranged to engage the said locking-lug of said barrel-unit and the connecting-element oi said tubular magazine to releasably secure said barrel-unit substantially rigidly to said frame-unit, an operating-lever for operating said takedown-screw, said operating-lever being arranged to lie in the slet of said fore-end in releasable engagement with the shouldered recess of said locking-block when in its normal inoperative position and to be withdrawn ircm said slot for operating said screw, and latch-mechanism mounted in said fore-end and arranged to releasably hold said operating-lever in the slot of said fore-end.

3. A takedown firearm, including in combination: a barrel-unit having a barrel-locking lug; a frame-unit including a tubular magazine having a connecting-element at the forward end thereof; a slotted fore-end arranged to cooperatively engage said frame-unit and said barrelunit; and takedown-means mounted in said slotted fore-end, said takedown-means comprising a locking-block secured in said fore-end and having a shouldered recess coextensive with the slot of said fore-end, a screw extending longitudinally through said locking-block and arranged to engage the said locking-lug of said barrel-unit and the connecting-element of said tubular magazine to releasably secure said barrel-unit substantially rigidly to said frame-unit, a screw-operating lever, and latch-mechanism mounted in said fore-end and arranged to secure said operatinglever to said screw to hold said operating-lever in the slot of said fore-end in releasable engagement with the shouldered recess of said lockingblock.

4. A takedown firearm, including in combination: a barrel-unit having a barrel-locking lug; a frame-unit including a tubular magazine having a connecting-element at the forward end thereof; a slotted fore-end arranged to cooperatively engage said frame-unit and said barrelunit; and takedown-means mounted in said slotted fore-end, said takedown-means comprising a locking-block secured in said fore-end and having a shouldered recess coextensive with the slot of said fore-end, a screw extending longitudinally through said locking-block and arranged to engage the said locking-lug of said barrel-unit and the connecting-element of said tubular magazine to releasably secure said barrel-unit suhstantially rigidly to said frame-unit, a screwoperating lever, and latch-mechanism including a link-member slidably mounted on said screw and arranged to secure said operating-lever to said screw for movement longitudinally relative thereto, and for movement into and out of the slot of said fore-end thereby to releasably hold said operating-lever in engagement with the shouldered recess of said locking-block.

5. A takedown firearm, including in combination: a barrel-unit having a barrel-locking lug; a frame-unit including a tubular magazine having a connecting-element at the forward end thereof; a slotted fore-end arranged to cooperatively engage said frame-unit and said barrelunit; and takedown-means mounted in said slotted fore-end, said takedown-means comprising a locking-block secured in said fore-end and having a shouldered recess coextensive with the slot of 

